The TAO has thrived and survived thousands of years for a good reason: what was applicable in the past is still applicable in the present; what was true in the past is still true today. Another testament to this universal truth is that "Tao Te Ching"-- the only book written by Lao Tzu -- is one of the most translated books in world literature -- probably only after the Bible.
The TAO is easy to understand but most controversial. The explanation is that there is no absolute truth about human wisdom, which is all about self-intuition and self-enlightenment. That is to say, your mind is uniquely yours, and your thinking is your own thinking.